Frank Welker was 62 in Scooby-Doo! The Mystery Begins when he played the character 'Scooby-Doo (voice)'.
That was over 15 years ago in 2009.
Today he is 78, and has starred in 386 movies in total, 87 of those since Scooby-Doo! The Mystery Begins was released.
In Scooby-Doo! The Mystery Begins, I think Frank Welker looks: